Like Tinker Bell, fiction can only live when the audience believes in fantasy. If the suspended disbelief falls to the ground, the crash jolts everyone into asking questions no author wants to hear. Why are we wasting our time? Is it worth staying to the end? Do we care any more?

I, like tens of millions around the world, have devoted dozens of hours to watching Game of Thrones. The series’ success has baffled its critics. “It’s only tits and dragons,” cried Ian McShane, somewhat ungraciously as Game of Thrones had given him a part along with virtually everyone else in Britain with an Equity card.

Ungracious and unfair too. Game of Thrones wasn’t written to show naked women on television. It is an adaptation of George R. R. Martin’s novels, which are a bit more than mere sword and sorcery. Martin’s vast plot gave HBO the material for a vast television drama with a clear direction of travel. Most US box sets meander. HBO and its rivals commission one series at a time. If the audience falls off, the show is cancelled. The producers cannot create a coherent whole with a beginning, middle and end because they don’t know when the end will come. The standard experience of watching a US mega-series in its entirety is to my mind one of disappointment. It just stops with a confected conclusion that feels as if it has been thrown together. There’s no sense of ending, of everything you have seen before rising to this point.

Game of Thrones was a clear story from one writer’s mind. If the television adaptation failed, Martin would doubtless be disappointed. But he would still follow his plots until they were resolved. Whatever happened in the accountants’ office at HBO, his novels would go on to a destination of his choosing.

Martin gave HBO more than narrative drive. He gave it dialogue far above the low standard television often accepts. A few of his phrases have entered the language. “Winter is coming.” “When you play the Game of Thrones, you win or die.” But the novels are packed with cynical and memorable lines about power and vice that HBO merely needed to copy and paste: “People often claim to hunger for truth, but seldom like the taste when it’s served up.” “There is no creature on earth half so terrifying as a truly just man.” “Power resides where men believe it resides. No more and no less.”

The cynicism, or perhaps I should call it realism, about human motivation comes in part from Martin’s plundering of the cruelties of medieval history. With Sansa Stark’s resemblance to Anne Neville, Tywin Lannister to Warwick the Kingmaker, and Robb Stark’s fit with Edward IV, Game of Thrones is the most successful representation of the Wars of the Roses since Shakespeare. Ramsay Bolton and King Joffrey aside, even its apparent villains are not wholly rotten. Far from being a comfort, the inability to place characters in boxes adds to the sense of uncertainty the novels create. They fit our pessimistic times. You can never be sure if someone you thought you knew to be good will turn vicious and stupid.